AIP-23 proof kinds: agent-witness-checkpoint, a checkpoint of the hosted agents witness log (log name, size, RFC 9162 root, the witness, the chain where it is notarized, the merge delay)

aips/aip23-kinds/KINDS.json

@@ -572,6 +572,67 @@
    "added": "2026-10-18",
    "vector": "secret-access.json"
   },
+  {
+   "kind": "agent-witness-checkpoint",
+   "statementKind": "aere-proof-of-agent-witness-checkpoint",
+   "envelopeKind": "aere-proof-of-agent-witness-checkpoint-attestation",
+   "fields": [
+    {
+     "name": "root",
+     "type": "hash",
+     "note": "already a 32-byte hash (0x + 64 hex); any other form is refused, not hashed",
+     "values": "a 32-byte hash, 0x + 64 lowercase hex (the RFC 9162 root of the log)"
+    },
+    {
+     "name": "previous",
+     "type": "hash",
+     "note": "already a 32-byte hash (0x + 64 hex); any other form is refused, not hashed",
+     "values": "the statementHash of the checkpoint before, 0x + 64 lowercase hex (absent on the first)"
+    },
+    {
+     "name": "log",
+     "type": "plain",
+     "values": "1 to 256 printable ASCII characters without spaces (the log name)"
+    },
+    {
+     "name": "witness",
+     "type": "plain",
+     "values": "aere-witness: + 40 lowercase hex (derived from the ML-DSA-65 key of the witness)"
+    },
+    {
+     "name": "chainId",
+     "type": "plain",
+     "values": "a positive integer (the chain the checkpoints are notarized on)"
+    },
+    {
+     "name": "treeSize",
+     "type": "plain",
+     "values": "an integer >= 1 (the number of heads in the log)"
+    },
+    {
+     "name": "maxMergeDelay",
+     "type": "plain",
+     "values": "an integer number of seconds >= 1 (the maximum merge delay)"
+    },
+    {
+     "name": "createdAt",
+     "type": "plain",
+     "values": "an RFC 3339 time"
+    }
+   ],
+   "required": [
+    "root",
+    "log",
+    "witness",
+    "chainId",
+    "treeSize",
+    "maxMergeDelay",
+    "createdAt"
+   ],
+   "attests": "a checkpoint of the hosted agents witness log (in the form of a transparency log checkpoint: log name, size, RFC 9162 root): the size and root of the tree of the agent ledger heads it received, the previous checkpoint (statementHash), the witness id (derived from its ML-DSA-65 key, which signs the envelope), the chain on which checkpoints are notarized and the maximum merge delay in seconds; the leaves are digests of signed heads, nothing of any ledger",
+   "added": "2026-10-19",
+   "vector": "agent-witness-checkpoint.json"
+  },
   {
    "kind": "ai",
    "statementKind": "aere-proof-of-ai",

aips/aip23-kinds/README.md

@@ -41,6 +41,7 @@ ABSENT). Change one field of a statement and it is INVALID at the integrity leve
 | settlement (added 2026-09-28) | `aere-proof-of-settlement` | `chainId`, `txHash`, `blockHash`, `amount`, `asset`, `createdAt` | a settlement on a chain: its transaction and block (32-byte hashes carried as they are, never re-hashed), amount and asset |
 | provenance (added 2026-09-28) | `aere-proof-of-provenance` | `subjectHash`, `parents`, `createdAt` | an artifact (digest) was produced from a non-empty list of parents (digests), by a process (digest), by an actor |
 | secret-access (added 2026-10-18) | `aere-proof-of-secret-access` | `service`, `operation`, `verdict`, `presentationHash`, `createdAt` | a secrets service judged one request (put, get, metadata, rotate, revoke-version, grant, revoke or list) on a named secret and version: the verdict and the rules that decided it, the presented identity (presentation digest) and the request it was signed for (request digest), the holder and presenter when verified (claimed ones are named as claimed), the grant and the policy (digest); never the value. Its values have a fixed vocabulary (KINDS.json, values) |
+| agent-witness-checkpoint (added 2026-10-19) | `aere-proof-of-agent-witness-checkpoint` | `root`, `log`, `witness`, `chainId`, `treeSize`, `maxMergeDelay`, `createdAt` | a checkpoint of the hosted agents witness log (in the form of a transparency log checkpoint: log name, size, RFC 9162 root): the size and root of the tree of the agent ledger heads it received, the previous checkpoint (statementHash), the witness id (derived from its ML-DSA-65 key, which signs the envelope), the chain on which checkpoints are notarized and the maximum merge delay in seconds; the leaves are digests of signed heads, nothing of any ledger |
 | ai | `aere-proof-of-ai` | `model.name`, `createdAt` | an AI action: which model and version, which prompt, input and output (digests), which tools, which agent, who asked |
 | agent-decision (added 2026-09-29) | `aere-proof-of-agent-decision` | `policyHash`, `action`, `decision`, `createdAt` | an AI agent action was judged against a policy (by its hash): allowed or refused, and why; the action by the digest of its canonical JSON |
 

aips/aip23-kinds/agent-witness-checkpoint.json

@@ -0,0 +1,17 @@
+{
+ "v": 1,
+ "kind": "aere-proof-of-agent-witness-checkpoint-attestation",
+ "statement": {
+  "v": 1,
+  "kind": "aere-proof-of-agent-witness-checkpoint",
+  "root": "0x5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a5a",
+  "previous": "0x6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b6b",
+  "log": "aere-agent-witness/28001",
+  "witness": "aere-witness:7c7c7c7c7c7c7c7c7c7c7c7c7c7c7c7c7c7c7c7c",
+  "chainId": 28001,
+  "treeSize": 3,
+  "maxMergeDelay": 1800,
+  "createdAt": "2026-09-26T00:00:00Z"
+ },
+ "statementHash": "0x52c07602afdc773b6b2441b5899161a192b973ad4c9fcad52f6f4c1ef3ca2aca"
+}